AN ULTRA-DEEP NEAR-INFRARED SPECTRUM OF
... Several recent studies have shown that about half of the massive galaxies at z ∼ 2 are in a quiescent phase. Moreover, these galaxies are commonly found to be ultra-compact with half-light radii of ∼ 1 kpc. We have obtained a ∼ 29 hr spectrum of a typical quiescent, ultra-dense galaxy at z = 2.1865 ...
... Several recent studies have shown that about half of the massive galaxies at z ∼ 2 are in a quiescent phase. Moreover, these galaxies are commonly found to be ultra-compact with half-light radii of ∼ 1 kpc. We have obtained a ∼ 29 hr spectrum of a typical quiescent, ultra-dense galaxy at z = 2.1865 ...
Massive z~1.3 evolved galaxies revealed
... predict such regular, massive disk systems at z > 1. However, it could be an exceptional case. Evolved galaxies have been discovered at z ≥ 1.5 (Soifer et al. 1999; Benitez et al. 1999; Stiavelli et al. 1999) but their small stellar masses do not provide severe constraints. The search for massive ev ...
... predict such regular, massive disk systems at z > 1. However, it could be an exceptional case. Evolved galaxies have been discovered at z ≥ 1.5 (Soifer et al. 1999; Benitez et al. 1999; Stiavelli et al. 1999) but their small stellar masses do not provide severe constraints. The search for massive ev ...
Turbulent Flow-Driven Molecular Cloud Formation: A Solution to the
... yet the ages of the stars produced by these clouds provide uniquely detailed constraints on cloud ages that are not obtainable in any other way (e.g., Hartmann et al. 1991; Feigelson 1996). Because of the importance of the stellar population ages, it is worth reviewing the situation in some detail, ...
... yet the ages of the stars produced by these clouds provide uniquely detailed constraints on cloud ages that are not obtainable in any other way (e.g., Hartmann et al. 1991; Feigelson 1996). Because of the importance of the stellar population ages, it is worth reviewing the situation in some detail, ...
Masses, Radii, and Equation of State of Neutron Stars
... to that of neutron star cores (see section 4.2). Theoretical work is guided by the well developed effective field theory approaches and the rapidly developing QCD calculations but there remain very large uncertainties in our understanding of the actual compositions of the cores. Open questions inclu ...
... to that of neutron star cores (see section 4.2). Theoretical work is guided by the well developed effective field theory approaches and the rapidly developing QCD calculations but there remain very large uncertainties in our understanding of the actual compositions of the cores. Open questions inclu ...
PH607lec11
... It suggests that there might be an upper ceiling to how large a galaxy can grow. Perhaps when a galaxy gets to be very large, its gravity is so strong that it rips up smaller galaxies that pass nearby before they can join it. Another question is why, if all galaxies are mergers of smaller ones, many ...
... It suggests that there might be an upper ceiling to how large a galaxy can grow. Perhaps when a galaxy gets to be very large, its gravity is so strong that it rips up smaller galaxies that pass nearby before they can join it. Another question is why, if all galaxies are mergers of smaller ones, many ...
Less than 15 percent of star formation in massive galaxies is
... …it was believed that the evolution of the merger rate could drive the decrease of the SFR density ...
... …it was believed that the evolution of the merger rate could drive the decrease of the SFR density ...
The GalMer database: galaxy mergers in the virtual observatory*
... the physics of galaxy formation through hierarchical merging, it is necessary to simulate galaxy interactions varying a large number of parameters, e.g. morphological types, mass ratios, orbital configurations. On the one hand, these simulations have to be performed in a cosmological context, capabl ...
... the physics of galaxy formation through hierarchical merging, it is necessary to simulate galaxy interactions varying a large number of parameters, e.g. morphological types, mass ratios, orbital configurations. On the one hand, these simulations have to be performed in a cosmological context, capabl ...
CLUSTER MAGNETIC FIELDS - NED
... (Dreher et al. 1987). Examples of this phenomenon are shown in (Figure 5). Moreover, the change in position angle from short to long wavelengths is much larger than π radians in many cases, whereas the fractional polarization remains constant. This result is critical for interpreting the large RMs f ...
... (Dreher et al. 1987). Examples of this phenomenon are shown in (Figure 5). Moreover, the change in position angle from short to long wavelengths is much larger than π radians in many cases, whereas the fractional polarization remains constant. This result is critical for interpreting the large RMs f ...
ATLASGAL -- The APEX telescope large area survey of the galaxy at
... Context. Thanks to its excellent 5100 m high site in Chajnantor, the Atacama Pathfinder Experiment (APEX) systematically explores the southern sky at submillimeter wavelengths, in both continuum and spectral line emission. Studying continuum emission from interstellar dust is essential to locating t ...
... Context. Thanks to its excellent 5100 m high site in Chajnantor, the Atacama Pathfinder Experiment (APEX) systematically explores the southern sky at submillimeter wavelengths, in both continuum and spectral line emission. Studying continuum emission from interstellar dust is essential to locating t ...
THE GREAT AGN DEBATE `AGN VS STARBURST
... nucleus that is defined by its spectral line emission. These systems show weak nuclear emission-line regions, and no other signatures of AGN. There is debate if they are actually AGN, if so they constitute the lowest-luminosity class of radio-quiet AGN. Radio Loud AGN 8. Radio Loud AGN are types of ...
... nucleus that is defined by its spectral line emission. These systems show weak nuclear emission-line regions, and no other signatures of AGN. There is debate if they are actually AGN, if so they constitute the lowest-luminosity class of radio-quiet AGN. Radio Loud AGN 8. Radio Loud AGN are types of ...
Historical introduction
... Lecture 1 Harlow Shapley and the distance to the centre of the Galaxy, 1918 ...
... Lecture 1 Harlow Shapley and the distance to the centre of the Galaxy, 1918 ...
Galaxies and Active Galaxies
... the amount of visible, luminous matter falls off at large distances from the center. • In elliptical galaxies, the gravity of the visible matter is not strong enough to accelerate the stars as much as they are. • Something else must be adding to the gravity of the galaxies without shining. March 7, ...
... the amount of visible, luminous matter falls off at large distances from the center. • In elliptical galaxies, the gravity of the visible matter is not strong enough to accelerate the stars as much as they are. • Something else must be adding to the gravity of the galaxies without shining. March 7, ...
S282_2 Introduction to active galaxies
... Normal galaxies Normal galaxies are made up of stars and (in the case of spiral and irregular galaxies) gas and dust. Their spectra consist of the sum of the spectra of these components. The optical spectra of normal stars are continuous spectra overlaid by absorption lines (Figure 1). There are tw ...
... Normal galaxies Normal galaxies are made up of stars and (in the case of spiral and irregular galaxies) gas and dust. Their spectra consist of the sum of the spectra of these components. The optical spectra of normal stars are continuous spectra overlaid by absorption lines (Figure 1). There are tw ...
Five Years of Swift Science: GRBs and More!
... Thermonuclear detonation of accumulated accretion on white dwarf ...
... Thermonuclear detonation of accumulated accretion on white dwarf ...
In Pursuit of the Least Luminous Galaxies
... tens (Mhalo > 106 M , [8]) or even hundreds of thousands (Mhalo > 105 M , [9]) of dark matter halos around the Milky Way. In light of this “missing satellite problem”, great attention has been paid to the total number of Milky Way dwarf galaxies. However, this is only one metric with which to lear ...
... tens (Mhalo > 106 M , [8]) or even hundreds of thousands (Mhalo > 105 M , [9]) of dark matter halos around the Milky Way. In light of this “missing satellite problem”, great attention has been paid to the total number of Milky Way dwarf galaxies. However, this is only one metric with which to lear ...
Harvesting ALFALFA: Discovering Galaxies in the Pisces
... and peculiar velocities of galaxies and clusters to determine the underlying distribution of dark matter in the large scale structures of the universe. PPS has been found to be wall of clusters roughly 5h-1 Mpc to 10h-1 Mpc deep extending at least 50h-1 Mpc from the Perseus to Pegasus with a signifi ...
... and peculiar velocities of galaxies and clusters to determine the underlying distribution of dark matter in the large scale structures of the universe. PPS has been found to be wall of clusters roughly 5h-1 Mpc to 10h-1 Mpc deep extending at least 50h-1 Mpc from the Perseus to Pegasus with a signifi ...
Chapter 17
... (iv) Cold dark matter; an exotic form of matter, moving at relatively slow speed, which can be detected only by its gravitational interactions; it appears to be quite abundant throughout the universe. 8. It seems that the universe is only about 4% normal matter and 20% dark matter, the remaining 76% ...
... (iv) Cold dark matter; an exotic form of matter, moving at relatively slow speed, which can be detected only by its gravitational interactions; it appears to be quite abundant throughout the universe. 8. It seems that the universe is only about 4% normal matter and 20% dark matter, the remaining 76% ...
FINAL PROGRAM - Drifting through the Cosmic Web
... (Poster) Weak Lensing Signatures of the Connexion between Massive Dark Matter Halos and the Cosmic Web ...
... (Poster) Weak Lensing Signatures of the Connexion between Massive Dark Matter Halos and the Cosmic Web ...
disks surviving the radiation pressure of radio pulsars
... inclination angles. The mass flow rate in quiescent phases of accretion-driven millisecond pulsars can occasionally drop to values low enough that the inner radius of the disk goes beyond the light cylinder. The possibilities considered here may be relevant for the evolution of spun-up X-ray binarie ...
... inclination angles. The mass flow rate in quiescent phases of accretion-driven millisecond pulsars can occasionally drop to values low enough that the inner radius of the disk goes beyond the light cylinder. The possibilities considered here may be relevant for the evolution of spun-up X-ray binarie ...
Matter Cycle in the Interstellar Medium (ISM)
... About reflection nebulae: spectrum of the Pleiades Nebula by Vesto Slipher (Lowell Obs.) ➙ replica of stellar spectra ⇒ concluded there must be reflection by “small particles” ...
... About reflection nebulae: spectrum of the Pleiades Nebula by Vesto Slipher (Lowell Obs.) ➙ replica of stellar spectra ⇒ concluded there must be reflection by “small particles” ...
Clusters of Galaxies
... 1. Rotation Curves in Galaxies: The rotation velocities of galaxies at large radii are constant. This is not what one would expect if the luminous matter (stars and gas) were all the matter. One can work out what the Dark Matter “Halo” looks like from this. 2. Velocities in Clusters of Galaxies: A ...
... 1. Rotation Curves in Galaxies: The rotation velocities of galaxies at large radii are constant. This is not what one would expect if the luminous matter (stars and gas) were all the matter. One can work out what the Dark Matter “Halo” looks like from this. 2. Velocities in Clusters of Galaxies: A ...
Comparing molecular gas across cosmic time
... In this section, we systematically compare all of the overlapping properties of the objects in Table 1. Figure 1 shows the distribution of the data listed in Table 1 in the radius-velocity plane, which are the most directly observable quantities available for our sample. Broadly speaking, the object ...
... In this section, we systematically compare all of the overlapping properties of the objects in Table 1. Figure 1 shows the distribution of the data listed in Table 1 in the radius-velocity plane, which are the most directly observable quantities available for our sample. Broadly speaking, the object ...
Chapman
... powered by star formation. If SF lasts for ~108 yr, significant stellar mass formed • Much rarer than other samples, but higher inferred SFR, likely contribute significantly to SFR density at high z ...
... powered by star formation. If SF lasts for ~108 yr, significant stellar mass formed • Much rarer than other samples, but higher inferred SFR, likely contribute significantly to SFR density at high z ...
Formation of millisecond pulsars with CO white dwarf companions–I
... that the neutron star does not accrete any significant amount of matter given that its accretion is limited by the Eddington luminosity corresponding to a maximum accretion rate of ∼10−8 M yr−1 , depending on the exact chemical composition of the accreted material and the geometry of its flow. It h ...
... that the neutron star does not accrete any significant amount of matter given that its accretion is limited by the Eddington luminosity corresponding to a maximum accretion rate of ∼10−8 M yr−1 , depending on the exact chemical composition of the accreted material and the geometry of its flow. It h ...
Astrophysical X-ray source
Astrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays.There are a number of types of astrophysical objects which emit X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some solar system bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons be relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.Furthermore, celestial entities in space are discussed as celestial X-ray sources. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.